The impact of health literacy: associations with disease activity and medication prescription in patients with rheumatoid arthritis.

OBJECTIVE: The aim of this study was to explore the longitudinal associations between health literacy profiles and disease activity and medication prescription in patients with RA. METHODS: Patients with RA who previously completed the Health Literacy Questionnaire (HLQ) and were assigned 1 of 10 distinct health literacy profiles based on cluster analysis were further aggregated into three groups: 'several health literacy limitations', 'some health literacy limitations' and 'good health literacy'. Linear mixed modelling (LMM) was used to analyse the association between health literacy groups and disease activity over the course of 1 year. Chi-squared tests and logistic regression analyses were used to compare medication prescriptions between the groups. RESULTS: A total of 108 patients with RA were included. LMM showed a significant effect of health literacy group on disease activity over time (P = 0.010). Patients with 'good health literacy' had significantly lower disease activity over time [28-joint DAS with ESR (DAS28-ESR) = 2.4] than patients with 'several health literacy limitations' (DAS28-ESR = 3.1), independent of age, gender and education level. Patients with 'good health literacy' were most often prescribed a biologic DMARD (50%), whereas patients with 'some health literacy limitations' more commonly received a conventional synthetic DMARD only [72.7%; odds ratio (OR) 4.24], and patients with 'several health literacy limitations' were more often prescribed prednisolone (52.4%; OR 3.56). CONCLUSION: Significant differences in longitudinal disease activity and medication prescription were observed between groups with different health literacy levels. These results stress the importance of insights into the role of health literacy in treatment and outcomes in patients with RA.

A multicomponent positive psychology intervention for euthymic patients with bipolar disorder to improve mental well-being and personal recovery: A pragmatic randomized controlled trial.

OBJECTIVE: Mental well-being and personal recovery are important treatment targets for patients with bipolar disorder (BD). The goal of this study was to evaluate the effectiveness of an 8-week group multicomponent positive psychology intervention (PPI) for euthymic patients with BD as an adjunct to treatment as usual (TAU) compared to TAU alone. METHODS: Patients with BD were randomized to receive TAU (n = 43) or the PPI in addition to TAU (n = 54). The primary outcome was well being measured with the Mental Health Continuum-Short Form. Personal recovery was measured with the Questionnaire about the Process of Recovery. Data were collected at baseline, mid-treatment, post-treatment and 6- and 12-month follow-up. Life chart interviews were conducted at 12 months to retrospectively assess recurrence of depression and mania. RESULTS: Significant group-by-time interaction effects for well-being and personal recovery were found favouring the PPI. At post-treatment, between-group differences were significant for well-being (d = 0.77) and personal recovery (d = 0.76). Between-group effects for well-being were still significant at 6-month follow-up (d = 0.72). Effects on well-being and personal recovery within the intervention group were sustained until 12-month follow-up. Survival analyses showed no significant differences in time to recurrence. CONCLUSIONS: The multicomponent PPI evaluated in this study is effective in improving mental well-being and personal recovery in euthymic patients with BD and would therefore be a valuable addition to the current treatment of euthymic BD patients. The fact that the study was carried out in a pragmatic RCT demonstrates that this intervention can be applied in a real-world clinical setting.

Exploring mental health dynamics during eating disorder treatment: A psychometric network study with panel data.

To explore mental health associations during eating disorder (ED) treatment. Based on the dual-continua model of mental health, general and ED-specific psychopathology, as well as emotional, psychological, and social well-being were considered as mental health domains.Network analyses with panel data were applied to explore within- (temporal and contemporaneous networks) and between-person effects in a sample of 1250 female ED patients during 12 months of outpatient treatment. The associations between the domains and their centrality were examined. Autoregressive and cross-lagged effects were also estimated.ED psychopathology was the most central domain in the temporal network. ED psychopathology changes predicted further ED psychopathology changes and small changes in the other domains. Weak bi-directional associations were found between changes in the well-being domains and general psychopathology. In contrast to the temporal network, ED psychopathology was the least central and psychological well-being the most central domain in the contemporaneous and between-subjects networks. This suggests a central role of psychological well-being for experiencing mental health within time points.ED psychopathology may change relatively independent from other mental health domains. Well-being domains may be considered as more stable aspects of mental health.

Generalized pain hypersensitivity and associated factors in gout.

OBJECTIVES: Previous studies have indicated that a sizeable proportion of patients with inflammatory arthritis present with features characteristic of central pain sensitization. However, this has not yet been examined in patients with gout. The objective of this study was to explore the presence of generalized pain hypersensitivity and associated factors in patients with diagnosed gout. METHODS: A cross-sectional survey was performed in outpatients with crystal proven gout using the generalized pain questionnaire (GPQ) to screen for the presence of generalized pain hypersensitivity. Additional self-reported socio-demographic and medical information was collected and several patient-reported outcome measures were completed. Univariable logistic regressions and multivariable LASSO regression analysis with 10-fold cross-validation was used to explore relationships with patient characteristics, clinical features and PROMs. RESULTS: Of the 97 included patients (84.5% male; mean (s.d.) age: 68.9 ± 11.9 years), 20 patients (20.6%, 95% CI: 13.0, 30.0) reported possible generalized pain hypersensitivity defined as a GPQ score ≥11 (range: 0-28; mean (s.d.) GPQ: 6.3 ± 5.3). Lower age, concomitant fibromyalgia and more experienced difficulties in performing their social role were independently associated with generalized pain hypersensitivity. Notably, use of urate lowering therapy was significantly lower in those with generalized pain hypersensitivity. CONCLUSIONS: Generalized pain hypersensitivity appears to be quite common in gout, despite its more intermittent nature compared with other inflammatory arthritides. As this kind of pain does not respond well to regular treatment, screening for non-inflammatory pain may be important for improving pain management in gout.

Disentangling between- and within-person associations of psychological distress and mental well-being: An experience sampling study examining the dual continua model of mental health among university students.

The dual continua model assumes that psychological distress and mental well-being are two related, yet distinct dimensions of mental health. Previous studies did convincingly show the distinctiveness of these two dimensions using mainly cross-sectional research. Despite the importance to distinguish between- and within-person associations in psychological theories, to date, no study specifically distinguished between- and within-person associations for the relationship between distress and well-being. Therefore, the objective of this study was to validate whether the dual continua model actually holds when examined within individuals. Intensive longitudinal data were collected through experience sampling. The sample included 25 university students (mean age = 23.50 years, 56% female), who completed a baseline questionnaire as well as momentary measures of psychological distress and mental well-being three times per day for two weeks. 1,014 timepoints were analyzed using multilevel models and person-mean centering was applied to distinguish between- and within person associations. A significant moderate negative between-person association was found for the relationship between psychological distress and mental well-being (ß = -.363, marginal R 2 = 0.15, p < .001). The within-person association was also significant and similar in magnitude (ß = -.432, marginal R 2 = 0.18, p < .001) at the group level. Individual within-person associations between distress and well-being varied substantially, but were negative for almost all participants. This study is an important step towards validating the applicability and universality of this widely used model. The current findings provide preliminary evidence that the dual continua model does not only hold between people, but also on the level it is actually used for, namely within individual people.

Measurement properties of the Dutch-Flemish patient-reported outcomes measurement information system (PROMIS) physical function item bank and instruments: a systematic review.

BACKGROUND: Limitations in physical functioning are a big concern especially for patients with chronic or musculoskeletal diseases. Therefore, physical functioning is often used as a core outcome of treatments. The generic patient-reported outcomes information system (PROMIS) physical function (PF) item bank has shown potential to measure PF with better precision, interpretability and lower respondent burden compared with traditional patient-reported outcome measures. This study provides an overview of the current evidence on the quality of the measurement properties of the translated Dutch-Flemish PROMIS-PF item bank and its subdomains, and their derived short forms and computer adaptive tests (CATs). METHODS: PubMed was searched up to June 17th 2020 for validation studies of Dutch-Flemish PROMIS-PF in Dutch and Flemish adults. Quality assessment of the included studies was conducted using the COSMIN Risk of bias checklist. The COSMIN criteria for good measurement properties were used to judge the results of the studies, which were adjusted and added to where needed for this review, in the context of IRT instruments and item banks. The quality of evidence was summarized for each measurement property based on the Grading of Recommendation Assessment, Development, and Evaluation (GRADE) approach. RESULTS: Eleven studies were included, evaluating the PROMIS-PF item bank, the Upper Extremity (UE) subdomain, and/or their derived short forms and CATs in different clinical populations. There is evidence for sufficient structural validity, measurement precision, construct validity, and cross-cultural validity of the Dutch-Flemish PROMIS-PF item bank. The upper extremity subdomain item bank shows high quality evidence for structural validity and measurement precision. Content validity of these item banks has not been thoroughly demonstrated in a Dutch-Flemish population. Furthermore, the derived instruments have far less robust evidence: there are fewer validation studies available and none examined their performance as stand-alone administered instruments. CONCLUSIONS: The first studies into the Dutch-Flemish PROMIS-PF item bank and the UE subdomain show promising results, with especially high quality evidence for sufficient structural validity and measurement precision. However, more studies, and with higher methodological quality, are needed to study the instruments derived from these item banks. These studies should also evaluate content validity, reliability and responsiveness.

Web-based self-help intervention for partners of cancer patients based on acceptance and commitment therapy and self-compassion training: a randomized controlled trial with automated versus personal feedback.

PURPOSE: To evaluate the effectiveness of two versions (personal or automated feedback) of a psychological Web-based self-help intervention targeting partners of cancer patients. The intervention was based on acceptance and commitment therapy (ACT) and self-compassion training. Participants' adherence and their satisfaction were also studied. METHODS: Two hundred three partners of patients with heterogeneous entities of cancer were randomized into three conditions: personal feedback (PF) (n = 67), automated feedback (AF) (n = 70), or waiting list (WL) control (n = 66). Participants completed measures at baseline (T0) and post-intervention (T1; 3 months after baseline) to assess psychological distress (HADS; primary outcome), positive mental health, caregiver strain, general health (secondary outcomes), posttraumatic growth, resilience, self-compassion, psychological flexibility, sense of mastery, and relational communication style (process measures). Participants in the two experimental conditions also completed these measures at follow-up (T2; 6 months after baseline). RESULTS: There was no significant difference in change in psychological distress, positive mental health, caregiver strain and general health from T0 to T1 for either of the experimental conditions compared with the WL-condition. However, when compared to a WL-condition, the PF-condition was effective in increasing psychological flexibility (effect size d = 0.49) and resilience (d = 0.12) and decreasing overprotection (d = 0.25), and the AF-condition was effective in reducing overprotection (d = 0.36) and improving protective buffering (d = 0.36). At follow-up, the PF-condition was more effective than the AF-condition for improving mental health (d = 0.36), psychological flexibility (d = 0.60), mastery (d = 0.48), and protective buffering (d = 0.24). Participants positively appreciated the intervention and 69% participants were adherent. CONCLUSION: This study demonstrates that a Web-based intervention based on ACT and self-compassion training with automated or personal feedback does not seem to improve psychological distress; however, it may have the potential to support partners of cancer patients to cope with the difficult situation they are facing. The condition with personal feedback seemed to be more beneficial.

Development and preliminary evaluation of the QUALIKO: an observational quality of life instrument for patients with Korsakoff's syndrome.

BACKGROUND: To develop a Korsakoff-specific measure of quality of life (QoL), to be rated by professional caregivers, and to field-test its psychometric properties in a sample of patients with Korsakoff's syndrome (KS) living in a specialized nursing home. METHODS: A research version of the QUALIKO was developed based on an existing instrument for dementia (the QUALIDEM), literature review and two rounds of surveys among expert professionals involved in the care for patients with KS. Next, QoL was independently rated using the preliminary QUALIKO for 77 patients with KS by two primary caregivers. RESULTS: The research QUALIKO consisted of 48 items describing observable behaviors across ten aspects of QoL relevant to patients with KS. Six items demonstrated poor scalability in the field test. The remaining 42 items all formed subscales with moderate to strong scalability according to Mokken scale analysis. Reliability was acceptable to good across both raters for all subscales (Mokken rho's = 0.70-0.90), except for the two 2-item subscales of negative affect and positive self-image (Mokken rho's = 0.47-0.71). Inter-observer agreement was excellent for five subscales (ICCs = 0.75-0.89) and fair to moderate for the other five subscales (ICCs = 0.59-0.72). The multidimensional internal structure was confirmed and all subscales were significantly correlated with primary caregivers' global ratings of QoL except for positive self-image. Missing item values were low and floor and ceiling effects acceptable for most subscales. CONCLUSIONS: The QUALIKO holds promise as a feasible, reliable, and valid measure of QoL in residential KS patients. Future research in larger samples is needed to confirm the psychometric dimensionality of the instrument, to gather normative data and to examine its test-retest reliability.

The relationship between emotion regulation and well-being in patients with mental disorders: A meta-analysis.

BACKGROUND: The importance of both specific emotion regulation strategies and overall deficits in emotion regulation in the context of psychopathology is widely recognized. Besides alleviating psychological symptoms, improving mental well-being is increasingly considered important in treatment of people with mental disorders. However, no comprehensive meta-analysis on the relationship between emotion regulation and well-being in people with mental disorders has been conducted yet. OBJECTIVE: The aim of the current study was to synthesize and meta-analyze evidence regarding the relationship between emotion regulation and well-being in clinical samples across studies. METHOD: A systematic literature search was conducted in PsycINFO, PubMed and Scopus and 94 cross-sectional effect sizes from 35 studies were meta-analyzed to explore this relationship. To be eligible for the meta-analysis, studies had to include a clinical sample, assess at least one specific emotion regulation strategy or overall deficits in emotion regulation and include well-being as outcome. RESULTS: The findings showed significant small to moderate negative relationships with well-being for the strategies avoidance (r = -0.31) and rumination (r = -0.19) and positive relationships with reappraisal (r = 0.19) and acceptance (r = 0.42). Grouping together putative adaptive and maladaptive strategies revealed similar sized relationships with well-being in the expected direction. Overall deficits in emotion regulation showed a negative moderate correlation with well-being (r = -0.47). No substantial difference in relationships was found when clustering studies into hedonic and eudaimonic well-being. CONCLUSION: Our findings suggest that emotion regulation is not merely related with psychopathology, but also with well-being in general as well as hedonic and eudaimonic well-being. Therefore, it might also be important to improve emotion regulation when aiming to improve well-being in people with mental disorders.

Development and validation of a patient-reported gout attack intensity score for use in gout clinical studies.

OBJECTIVE: Inflammation-related symptoms such as pain, swelling and tenderness of the affected joint are frequently assessed using 5-point diary rating scales in gout clinical trials. Combining these into a single gout attack symptom intensity score may be a useful summary measure for these data, which is potentially more responsive to change compared with the individual components. The objective of this study was to develop a patient-reported gout flare intensity score, the Gout Attack Intensity Score (GAIS), for use in clinical studies, that includes components for gout-related pain, swelling and tenderness. METHODS: Data from a randomized controlled trial comparing anakinra to standard of care for the treatment of acute gout attacks were used for this study. A 7-day flare diary was completed by patients, including questions relating to intensity of pain, swelling and tenderness (5-point rating scales). Scalability of these items was assessed using Mokken Scale Analysis, and reliability using greatest lower bound reliability coefficients. Known-groups validity was evaluated, as well as the responsiveness to change and the presence of floor and ceiling effects. RESULTS: Scalability of the single items was supported, and GAIS scores were reliable (greatest lower bound >0.80). GAIS scores demonstrated responsiveness to change with high effect sizes (>0.8), and discriminated better between responders and non-responders compared with its single-item components. No floor and ceiling effects were found. CONCLUSION: The GAIS seems to be a reliable and responsive instrument for assessing patient-reported gout attack intensity that may be used in gout clinical studies.

A systematic literature review of patient-reported outcome measures used in gout: an evaluation of their content and measurement properties.

BACKGROUND: Gout is a common, monosodium urate crystal-driven inflammatory arthritis. Besides its clinical manifestations, patients often also suffer from pain, physical impairment, emotional distress and work productivity loss, as a result of the disease. Patient-reported outcome measures (PROMs) are commonly used to assess these consequences of the disease. However, current instrument endorsements for measuring such outcomes in acute and chronic gout clinical settings are based on limited psychometric evidence. The objective of this systematic literature review was to identify currently available PROMs for gout, and to critically evaluate their content and psychometric properties, in order to evaluate the current status regarding PROMs for use in gout patients. METHODS: Systematic literature searches were performed in the PubMed and EMBASE databases. The methodological quality of included papers was appraised using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist, and evaluation of measurement properties (reliability, responsiveness, construct validity, floor and ceiling effects) was done in accordance with published quality criteria. Item content was appraised by linking health concepts to the International Classification of Functioning Disability and Health (ICF) framework. RESULTS: In total, 13 PROMs were identified, of which three were targeted specifically at gout patients. The majority of the PROMs were rated positively for content validity. For most instruments, limited evidence was available for construct validity and reliability. Instruments to assess pain scored well on responsiveness and floor and ceiling effects, but not much is known about their reliability in gout. CONCLUSIONS: The physical functioning subscale of the SF-36v2 (Short Form-36 item version 2) is the only PROM that had sufficient supporting evidence for all its psychometric properties. Many of the commonly used PROMs in gout are currently not yet well supported and more studies on their measurement properties are needed among both acute and chronic gout populations.

Psychometric properties and utility of the Responses to Positive Affect questionnaire (RPA) in a sample of people with bipolar disorder.

OBJECTIVES: To evaluate the psychometric properties of the Responses to Positive Affect (RPA) questionnaire in a sample of persons with bipolar disorder (BD). METHOD: Cross-sectional survey study with 107 persons with BD. The original 3-factor model of the RPA was compared with a 2-factor model. Construct validity was determined with measures of well-being, personal recovery, social role participation, and psychopathology and incremental validity was evaluated. RESULTS: The fit of the 3-factor model was acceptable for most fit indices. Subscores of the RPA revealed a significant relationship with aspects of well-being, personal recovery, and psychopathology. Dampening and self-focused positive rumination explained additional variance in personal recovery above and beyond well-being. CONCLUSIONS: The RPA is an internally consistent and valid tool to assess positive emotion regulation processes in persons with BD. Specifically, the processes of dampening and emotion-focused positive rumination seem to play an important role in BD.

Measuring personal recovery in people with bipolar disorder and exploring its relationship with well-being and social role participation.

The relevance of personal recovery receives increasing attention in mental health care and is also important for people with bipolar disorder (BD). There is a need for reliable and valid instruments measuring personal recovery. Therefore, the current study evaluated the psychometric properties of a Dutch translation of the Questionnaire about the Process of Recovery (QPR) in a sample of people with BD and explored the relationship with constructs of well-being, social role participation, and psychopathology. A cross-sectional survey study was conducted in which 102 people diagnosed with BD completed the QPR. Factor structure of the QPR was evaluated by conducting confirmatory factor analyses (CFA), and internal consistency was assessed by calculating reliability coefficients. Convergent validation measures assessed well-being, social role participation, and symptomatology. Incremental validity was determined by evaluating the ability of the QPR to explain variance in symptomatology above and beyond well-being. Findings of the CFA supported a unidimensional factor structure, and internal consistency estimates were excellent. Scores of the QPR showed strong correlations with convergent measures, but were only weakly associated with manic symptomatology. Moreover, personal recovery explained additional variance in symptoms of depression and anxiety above and beyond well-being, indicating incremental validity. The QPR appears to be a reliable and valid tool to assess personal recovery in people with BD. Our findings underline the importance of personal recovery in the context of treatment of BD. Personal recovery demonstrates a substantial overlap with well-being.

B-positive: a randomized controlled trial of a multicomponent positive psychology intervention for euthymic patients with bipolar disorder - study protocol and intervention development.

BACKGROUND: Bipolar disorder (BD) is characterized by recurrent (hypo)manic and depressive episodes, alternating with euthymic states in which patients are relatively symptom free. Besides clinical recovery, it is important to also strive for improvement of mental well-being and personal recovery. One prominent field focussing on the improvement of well-being is positive psychology. However, studies assessing the effects of positive psychology or personal recovery interventions for people with BD are scarce and have used weak methodological designs. The study described in this protocol article aims to assess the effectiveness of a multicomponent positive psychology intervention ("Living well with bipolar disorder") adjusted for people with BD in the euthymic phase to improve well-being and personal recovery. METHOD: The study concerns a pragmatic randomized multicenter trial. The principle objective of the study is to assess whether the positive psychology intervention offered to BD patients in remission in addition to usual care (CAU) is more effective than CAU. The study will include 112 participants randomized to either the experimental condition receiving the intervention in addition to CAU or the control condition receiving CAU. The study population are patients with BD I or II in the euthymic phase. The inclusion criteria are 1) diagnosis of BD I or BD II, 2) between the ages of 18-65, 3) four or more supportive sessions in the last year, and 4) only residual depressive or manic symptoms. Patients are excluded if they are in a depressive or manic episode, have current addiction problems or have optimal levels of well-being. Measurements take place at baseline, post-intervention and follow-up 6 and 12 months from baseline. Outcomes of measures include positive well-being, personal recovery, psychopathology, self-compassion, positive relationships, dampening of positive affect and relapse. DISCUSSION: The outlined study will be the first RCT examining the effects of a multicomponent positive psychology intervention for patients with bipolar disorder. Several limitations, including generalizability of the results and possible attrition issues, are discussed in advance. TRIAL REGISTRATION: This study has been registered in the Netherlands Trial Register ( NTR6729 ) on 12 October 2017.

Structural Validity of the World Assumption Scale.

The World Assumption Scale (WAS) is a frequently used measure in trauma research. The 32 items of the WAS are intended to represent eight assumptions about the benevolence of the world, the meaningfulness of events, and the worthiness of the self. Debate about the validity of the WAS is ongoing, particularly in terms of its empirical factor structure; some studies have confirmed a model of eight correlated factors whereas several other studies have not. The WAS items were administered to a clinical sample of patients who sought professional help because of posttraumatic complaints (n = 1,791) as well as a sample of healthcare professionals (n = 236). We split the clinical sample into three subsamples, then performed exploratory factor analysis using data from one subsample and tested the factor structure with confirmatory factor analysis using the other two subsamples. A consistent model of eight correlated factors was demonstrated, with almost all factors showing acceptable reliability, Cronbach's αs = .68-.84. We tested this factor model against data from the sample of healthcare professionals with increasingly stringent levels of invariance and found it to be scalar invariant (same structure, loadings, and thresholds). In a regression analysis, five factors showed significant associations with posttraumatic stress disorder (PTSD) symptoms, and two factors had unique associations with PTSD symptoms after we controlled for traumatic events: Self-Worth, ß = -.31; and Luck, ß = -.15. Future research should aim to distinguish between different assumptions and their individual influences on posttraumatic complaints.

Validation of the Mental Health Continuum-Short Form and the dual continua model of well-being and psychopathology in an adult mental health setting.

OBJECTIVE: The growing evidence for the dual continua model of psychopathology and well-being has important implications for measuring outcomes in mental health care. The aim of the current study is to validate a measure of well-being as well as the dual continua model in adults with mood, anxiety, personality, and developmental disorders. METHODS: 472 adult psychiatric outpatients filled out the Mental Health Continuum-Short Form (MHC-SF) and the Outcome Questionnaire before start of treatment. RESULTS: Confirmatory factor analyses (CFA) confirmed the three-factor structure of emotional, psychological, and social well-being of the MHC-SF. The dual continua model had the best fit in the complete sample and the different diagnostic groups. CONCLUSION: The MHC-SF is a reliable and valid instrument to measure well-being in the psychiatric population. Although relatively high correlations between psychopathology and well-being exist, the results underline the importance to measure well-being in addition to psychopathology in mental health care.

Measuring everyday functional competence using the Rasch assessment of everyday activity limitations (REAL) item bank.

OBJECTIVE: Traditional patient-reported physical function instruments often poorly differentiate patients with mild-to-moderate disability. We describe the development and psychometric evaluation of a generic item bank for measuring everyday activity limitations in outpatient populations. STUDY DESIGN AND SETTING: Seventy-two items generated from patient interviews and mapped to the International Classification of Functioning, Disability and Health (ICF) domestic life chapter were administered to 1128 adults representative of the Dutch population. The partial credit model was fitted to the item responses and evaluated with respect to its assumptions, model fit, and differential item functioning (DIF). Measurement performance of a computerized adaptive testing (CAT) algorithm was compared with the SF-36 physical functioning scale (PF-10). RESULTS: A final bank of 41 items was developed. All items demonstrated acceptable fit to the partial credit model and measurement invariance across age, sex, and educational level. Five- and ten-item CAT simulations were shown to have high measurement precision, which exceeded that of SF-36 physical functioning scale across the physical function continuum. Floor effects were absent for a 10-item empirical CAT simulation, and ceiling effects were low (13.5%) compared with SF-36 physical functioning (38.1%). CAT also discriminated better than SF-36 physical functioning between age groups, number of chronic conditions, and respondents with or without rheumatic conditions. CONCLUSION: The Rasch assessment of everyday activity limitations (REAL) item bank will hopefully prove a useful instrument for assessing everyday activity limitations. T-scores obtained using derived measures can be used to benchmark physical function outcomes against the general Dutch adult population.

The impact of non-response bias due to sampling in public health studies: A comparison of voluntary versus mandatory recruitment in a Dutch national survey on adolescent health.

BACKGROUND: In public health monitoring of young people it is critical to understand the effects of selective non-response, in particular when a controversial topic is involved like substance abuse or sexual behaviour. Research that is dependent upon voluntary subject participation is particularly vulnerable to sampling bias. As respondents whose participation is hardest to elicit on a voluntary basis are also more likely to report risk behaviour, this potentially leads to underestimation of risk factor prevalence. Inviting adolescents to participate in a home-sent postal survey is a typical voluntary recruitment strategy with high non-response, as opposed to mandatory participation during school time. This study examines the extent to which prevalence estimates of adolescent health-related characteristics are biased due to different sampling methods, and whether this also biases within-subject analyses. METHODS: Cross-sectional datasets collected in 2011 in Twente and IJsselland, two similar and adjacent regions in the Netherlands, were used. In total, 9360 youngsters in a mandatory sample (Twente) and 1952 youngsters in a voluntary sample (IJsselland) participated in the study. To test whether the samples differed on health-related variables, we conducted both univariate and multivariable logistic regression analyses controlling for any demographic difference between the samples. Additional multivariable logistic regressions were conducted to examine moderating effects of sampling method on associations between health-related variables. RESULTS: As expected, females, older individuals, as well as individuals with higher education levels, were over-represented in the voluntary sample, compared to the mandatory sample. Respondents in the voluntary sample tended to smoke less, consume less alcohol (ever, lifetime, and past four weeks), have better mental health, have better subjective health status, have more positive school experiences and have less sexual intercourse than respondents in the mandatory sample. No moderating effects were found for sampling method on associations between variables. CONCLUSIONS: This is one of first studies to provide strong evidence that voluntary recruitment may lead to a strong non-response bias in health-related prevalence estimates in adolescents, as compared to mandatory recruitment. The resulting underestimation in prevalence of health behaviours and well-being measures appeared large, up to a four-fold lower proportion for self-reported alcohol consumption. Correlations between variables, though, appeared to be insensitive to sampling bias.

[The Well-Being Measure - dementia: A validation study]. / Validatieonderzoek Welzijnsmeter-dementie.

The Well-Being Measure - dementia is a digital observation instrument that assesses the well-being of persons with dementia on four domains of quality of life: Mental well-being, Physical well-being, Participation, and Living arrangements. Its goal is to assess the well-being of persons with dementia in an easy and positive way. Besides illness-related symptoms and problems, the instrument also assesses positive aspects of functioning. It visualizes the results and provides specific behavioural advice to the caregivers. The goal of the present article is to conduct a first psychometric analysis: factor structure, reliability (Cronbach's alpha), concurrent, and convergent validity.Observations were carried out among 168 persons with dementia in eleven different small-scale psychogeriatric wards. Five existing instruments were used among 63 persons to validate the Well-Being Measure-dementia: quality of life, neuropsychiatric symptoms, care dependency, depression, and agitation.The expected factor structure was found in each of the four domains. Coefficients were high on the expected factor and low on the other factor(s). The scale means were on the positive side, but showed an adequate range and variability. Reliability was satisfactory to good. The relation with existing scales was moderate to strong. The pattern of relations was consistent with the measurement intentions of the different existing instruments.The Well-Being Measure - dementia appears to be a valid and reliable scale. Further studies should assess its test-retest reliability, sensitivity to change and relation with the course of dementia. Current experience shows that the instrument is also useful in everyday practice.

Acceptance and commitment therapy as a web-based intervention for depressive symptoms: randomised controlled trial.

BACKGROUND: Depression is a highly prevalent disorder, causing a large burden of disease and substantial economic costs. Web-based self-help interventions seem promising in promoting mental health. AIMS: To compare the efficacy of a guided web-based intervention based on acceptance and commitment therapy (ACT) with an active control (expressive writing) and a waiting-list control condition (Netherlands Trial Register NTR1296). METHOD: Adults with depressive symptoms from the general population were randomised to ACT (n = 82), expressive writing (n = 67) or waiting-list control (n = 87). The main outcome was reduction in depressive symptoms assessed with the Center for Epidemiological Studies - Depression scale. RESULTS: Significant reductions in depressive symptoms were found following the ACT intervention, compared with the control group (Cohen's d = 0.56) and the expressive writing intervention (d = 0.36). The effects were sustained at 6-month and 12-month follow-up. CONCLUSIONS: Acceptance and commitment therapy as a web-based public mental health intervention for adults with depressive symptoms can be effective and applicable.